Lawn mower



Patented Sept. 1936 UNITED sTATEs PATENT OFFICE LAWN Mownn John P. schwein, Los Angeles, cam. Application July s. 1935. serial No. 30,265

e claims. o1. se-zs) 'I'his invention relates to a lawn mower and more particularly pertains to lawn mowers of the manually impelled type inoluding'a revoluble cutter; the primary object of the invention being to 'provide a motor drive for the cutter adapted to operate the latter independent of the running gear of the mower whereby a lawn mower is produced which is adapted to be manually impelled and the cutting blades power driven thereby overcoming objectionable features incident to the ordinary manually operated type of lawn mower in which the propulsion of the rotary cutter is eifected through a driving connection from the traction wheels of the mower, and also incident to power driven lawn mowers in which both the traction wheels and the cutter are motor actuated.

Another object is to provide a manually impelled lawn mower having a power driven cutter in which operation of the cutter will assist but not effect zo forward movement of the mower during mowing operations whereby a minimum of manual effort is required in manipulating the mower.

Another object is to provide a lawn mower with a power driven cutter so operated as to be subject to control without the aid of clutch mechanism and in which the cutter may be placed in operation independent of movement of the mower by merely manipulating an electrical switch.

Another object is to provide a lawn mower in which a power driven cutter is arranged to project forward of the traction wheels of the mower so as to permit operation of the mower to effect a mowing action close to edges of lawns, bordered by upstanding edgings such as, curbs, walls and border plants. f

A further object isto provide an arrangement in a lawn mower of the` above character whereby the cutter may be driven either by motive power or from the traction wheels of the mowerthereby rendering the mower convertible from a power driven to a manually driven cutter. Another object is to provide a. chassis for the lawn mower so constructed as to afford a substantial mounting for the cutter and its operating '45 mechanism, embodying a housing or cover arrangement aifording a guard for the cutter and protection of the mechanism from cuttings.

Various additional objects and features of theA invention will appear and 4will be more fully understood from the following detailed description f of a present preferred embodiment thereof. reference for this 'purpose being had to the accompanying drawing, in which:

Fig. 1 is a view of the mower as seen in front elevation partly in vertical section:

Fig. 2 is a plan view of the mower:

Fig. 3 is a view in section and elevation taken on the line 3 3 of Fig. 1 as seen in the direction indicated by the arrows:

Fig. 4 is a detail in section as seen on the line 5 4 4 of Fig. 3 in the direction indicated by the arrows.

Referring to the drawing more specifically A and B indicate a pair of traction wheels each of which embodies an annular rim 'La disk 8 and a 10 hub 9; the rim and ldisk being here shown as formed integral and the hub being shown as embodying a flange II) aixed to the disk 8 by rivets II with the hub projecting from the inner face of the disk 8 in a manner common in lawn mower l5 wheel construction.

In carrying out the present invention each of the wheels A and B are revolubly mounted on the hub I2 of a gear wheel I3 which latter is arranged on the inner side of the wheel with its hub 20 I2 extending through the hub 9 of the latter. The gear wheels I3 are journalled on axles I4 formed on the ends of a shaft I5. The inner faces of the gear wheels I3 slidably abut against shoulders I6 at the outer ends of exteriorly threaded collars I'I 25 formed at the inner ends of the axles I4. Mounted on the outer ends of the axles are washers I8. held in place by cotter pins I9, which Washers overlie and slidably abut the hubs 9 and I2 whereby the traction wheels and gear wheels '30 are collectively retained on the axles I4. The traction wheels and gear wheels are designed nor- Y mally to be revoluble in either direction independent of each other excepting as to tendency of rota.- tion of the gear wheels I3 to effect rotation of the 35 traction wheel by reason of frictional engagel ment between the hubs thereof but in order to prevent driving of the gear wheels I3 on advance rotation of the traction wheels, an overrunning clutch C is interposed betweeneach of the trac- 40 tion wheels and its associated gear wheel, which clutchis here shown as embodying an annular ange 2U formed on the gear wheel I3 and having a series of teeth 2i on its inner periphery adapted to be engaged by a series of pawls 22 pivotally sup- 45 ported on the hub 9 as particularly shown in Fig. 3; the vpawls 22 extending in such direction as to permit free rotation of the gear wheels I3 in the direction of forward movement of the traction wheels relative to the latter and being 50 supported to gravitate into engagement with the teeth 2l to effect engagement therewith so that forward turning of the traction wheels may effect rotation .of the gear wheels in unison therewith when it is desired to effect driving of the gear 55 'ill wheels from the traction wheels. Manifestly the overrunning clutches permit retrograde movement of the traction wheels independent of the gear wheels. l

Carried on each end portion of the shaft i5 is a frame member D constituting a part of the mower chassis and which member embodies a plate 2d vprojecting over the inner face of the gear wheel i3 and formed with an opening through which the threaded collar il extends; the member D being held in place on the shaft it by a nut 25 screwed on the collar il and clamping the plate 2d against a ange 26 on the shaft l5.

The upper end portions of the frame members D are connected together by a tubular frame member 2i through which extends longitudinally a revcluble shaft 28 journalled in the end portions of the member 2 and having pinions 2li on the outer ends thereof which mesh with the gear wheels i3, and supported on the frame member 2i is an electric motor E which is geared to .the shaft 28 through aV series of speed reduction gears Sii affording a driving connection between the motor drive shaft and a stub shaft 3i which latter is tted with a gear wheel 32 meshing with a gear wheel 33 on the shaft 28. An electrical conductor F leads from the motor E to any suitable source of electrical current supply.

The plate 2d of each of the frame members D' is formed with a forwardly projecting portion 3d, as particularly shown in Fig. 3, and journalled in such portions is a revoluble shaft 35 carrying a series of spaced spirally arranged cutting blades St in a fashion common to lawn mower construcy tion. The ends of the shaft 35 are iltted with pinions 3l meshing with idler gears 38 which in turn intermesh with the gear wheels i3.

Each frame member D embodies'a demount1 able cover portion 39 which encompasses the marginal portion of the gear i3 and houses the gears 29, 3l, and 3e. The motor E and its gear connections to the shaft 28 are encased in a housing @il and projecting over the cutter 3B is a cover plate di extending between the plates 2d and leading from the frame member 2l forwardly and `downwardly in front' of the cutter with its outer lower margin spaced from the lower peripheral portion of the cutter.

Associated with the cutter blades 3811s a stationary blade 32 which is carried on the plates 2d, which blade cooperates with the blades et to eect a cutting action asis common in lawn mower construction.

it `will be noted that in the arrangement' shown the cutter comprising the blades Se is disposed so as to projectA forwardly ofthe traction wheels A and B. As a means for main'- taining the cutter in spaced relation to the ground and also for adjusting the spacing ofthe blades relative to the ground a pair of rollers i3 are mounted on the frame 'members'D to contact the ground forward-of the traction wheels A and B; the wheels B3 being carried on slide blocks dii mounted for vertical adjustment on the extensions 36 of the plates 2d.

The mower is equipped with a handle (not shown) connected thereto through the medium of yoke members d5 in a manner coon in lawn mower construction.

In the operation of the invention, on placing the motor E in operation-.the shaft 2d will be driven through the reduction gears 30, shaft 3i,

and gears 32 and 33, driving of the shaft 28 will effect driving of the gear wheels i3 through'the 'n By positioning the cutting accesos pinion 29, and rotationof the gear wheels it will operate through the idlerA gears 38 to drive the gears 3l? and thereby .rotate the blade carrying shaft 35 thus revolving the mower blades 3E,

. which latter rotate in a direction corresponding to the direction of rotation of the traction wheels Aand B on advancing the lawn mower. The mower may be easily. advanced and retracted by the operator and quickly stopped at the ends of the strokes thus permitting operation of the mower in a fashion similar to that employed in operating the ordinary carpet sweepers.

'During the driving of the gears i3 from the motor they will be driven at a peripheral speed exceeding that of the traction wheels A and B during forward movement of the mower at usual speeds, and accordingly manual impelling of the mower in 7a forwardv direction will be permitted while the motor E is in operation.

However, when the motor E is stationary forward movement of the mower will be opposed by reason of the pawls 22 of the clutch C when engaging the teeth 2i of the gear wheels it so that the latter will rotate in unison with the traction wheels A and B against resistance of driving of vthe blades et and.y turning over of the motor E from the gear wheel i3. The resistance to rotation of the gear wheel i3 is then so great as to render diiilcult `the manual impelling of the motor forwardly. However retrograde movement of the mower may be readily effected since the pawls 22 will then ride over the teeth El on retrograde rotation of the traction wheels. j

In event it is desired to eifectdriving of the mower from the traction wheels the driving connection between the motor and the gear wheels i 3 is placed out o'f operation as by detaching the pinions 29 from the shaft 28.

blades forward of the tractionwheels the mower is adapted to eiect a cutting action close to walls, edgings, trees and other upstanding objects on advancing the mower adjacent thereto.

I claim:

i. In a lawn mower, a pair of traction wheels, gear wheels having hubs on which said traction wheels are journalled, a shaft, axles on said shaft on which said gear wheels and traction wheels are .collectively carried, a frame carried by said axle,

a revoluble cutter mounted on said frame projecting forwardly of said traction wheels, gear connections between said gear wheels and said cutter for driving the latter, a motor carried by said frame, and means for driving said gear wheels from said motor.

2. The structure called for in claim 1 including overrunning clutches interposed between said traction wheels and said gear wheels.

3. In a lawn mower, a pair of traction wheels, gear wheels having hubs on which said traction wheels are journalled in sliding frictional contact with said hubs, a shaft, axles on said shaft on which said gear wheels and traction wheels are collectively carried, a frame carried by said axle, a revoluble cutter mounted on said frame projecting forwardly of said traction wheels,lgear con nections between said gear wheels and said cutter for driving thek latter, a motor carried by said .a frame, and means for driving said gear wheels from said motor. A

4. In a lawn mower, a pair of spaced housings, a shaft to which said housings are amxed,

axles on the ends of said shaft, gear wheels journalled on said axles arranged in said housings, a revoluble cutter carried by said housings. said cutter being arranged yto project forwardly of said gear wheels, gear connections between said cutter and said gear wheels. a motor carried by said housings. means for driving said gear wheels from said motor, and a pair of traction wheels mounted on said axles.

5. In a lawn mower, a pair of spaced housings, a shaft to which said housings are amxed, axles on the ends of said shaft, gear wheels journalled on said axles arranged in said housings, a revoluble cutter carried by said housings, gear connections between said cutter and said gear wheels,

a motor carried by said housings, means for driving said gear wheels from said motor, a pair of traction wheels cutter being arranged to project forwardly of said gear wheels, and rollers carried by said housmounted on said axles, saidy ings forwardly of said traction wheels cooperating with the latter to support said cutter in spaced relation to the ground.

6. In a lawn mower. a pair of spaced housings, a shaft to-which said housings are aiiixed, axles on the ends o! said shaft, gear wheels journalled on said axles arranged in said housings, a revoluble cutter carried by said housings, said cutter being arranged to project forwardly of said gear wheels, gear connections between said cutter and said gear wheels, a motor carried by said housings, means for driving said gear wheels from said motor, a pair of traction wheels mounted on said axles, and a guard housing extending over said cutter and projecting downwardly in front thereof.

JOHN P. SCHIELEIN. 

